Apparatus for conditioning the temperature of a fluid

ABSTRACT

This invention relates to an apparatus for conditioning the temperature of a fluid by utilizing a thermoplastic heat exchange apparatus comprised of a plurality of hollow tubes. The apparatus controls the temperature of a process fluid inside the heat exchanger by adjustment of a control valve that regulates the flow of an exchange fluid. The apparatus can be used to maintain the temperature of chemical baths and also to prepare discreet dispensed volumes of temperature controlled liquid. The device is chemically inert and has the ability to operate at elevated temperatures and also with corrosive and oxidizing liquids.

RELATED APPLICATIONS

[0001] This application claims priority to provisional application60/326,357 and is related to copending application filed concurrentlyherewith as U.S. Ser. No. 60/326,234, filed Oct. 1, 2001 underApplicants' reference number 200100292PCT (formerly MYKP-620).

FIELD OF INVENTION

[0002] This invention relates to an apparatus for conditioning thetemperature of a fluid by utilizing a thermoplastic heat exchangeapparatus comprised of a plurality of hollow tubes. The apparatuscontrols the temperature of a process fluid inside the heat exchanger byadjustment of a control valve which regulates the flow of an exchangefluid The apparatus has a fast response, is compact, chemically inert,and can operate at elevated temperatures.

BACKGROUND

[0003] Heat exchangers have been used in medical, automotive, andindustrial applications. Their efficiency and heat transfer capacity aredetermined by the thermal conductivity, flow distribution, and heattransfer surface area of the exchanger.

[0004] Examples of applications of heat exchanger use in semiconductormanufacturing where controlled heating of a liquid is often requiredinclude: sulfuric acid and hydrogen peroxide photoresist stripsolutions, hot phosphoric acid baths for silicon nitride and aluminummetal etching, ammonium hydroxide and hydrogen peroxide SC1 cleaningsolutions, hydrochloric acid and hydrogen peroxide SC2 cleaningsolutions, hot deionized water rinses, and heated organic amine basedphotoresist strippers.

[0005] Heating of chemical mechanical planarization, CMP, liquids andabrasive slurries can also be performed to control removal rates. Achemical mechanical slurry typically comprises solid abrasive materialslike alumina or silica abrasives, oxidizers like hydrogen peroxide, andeither acids or bases such as hydrochloric acid or ammonium hydroxide.

[0006] In many semiconductor manufacturing steps liquids with accuratelycontrolled temperature are dispensed onto substrates to form thin films.In these applications the temperature of the liquid has an effect on theuniformity and thickness of the final film.

[0007] Accurate and repeatable temperature conditioning of liquids suchas spin on dielectrics, photoresists, antireflective coatings, anddevelopers prior to dispense onto a stationary or spinning substraterequires heating or cooling of these liquids. This is often done byflowing the process liquid inside a relatively thick walledperfluorinated tube whose temperature is controlled on the outside ofthe tube with a flow of water.

[0008] Heat exchangers are devices which transfer energy between fluids.This is done by contacting one fluid, the process fluid, and a workingfluid or exchange fluid. These two fluids are physically separated fromeach other by the walls the material comprising the heat exchanger.Polymer based heat exchangers are commonly used for heating and coolingchemicals for many these applications due to its chemical inertness,high purity, and resistance to corrosion. However polymeric heatexchange devices are usually large because a large heat transfer surfacearea is required to effect a given temperature change due to the lowthermal conductivity of the polymers used in the device. Such a largesize has not made it practical to use such devices on semiconductorprocess tools

[0009] Gas to liquid finned heat exchangers are used in conditioninggases used in lasers. These exchangers are commonly made of metals whichare not suitable for use with corrosive chemicals or gases and canproduce particles when moisture is present.

[0010] U.S. Pat. No. 3,315,740 discloses a method of bonding tubestogether by fusion for use in heat exchangers. Tubes of a thermoplasticmaterial are gathered in a manner such that the end portions of thetubes are in a contacting parallel relationship. Canadian Patent 1252082teaches the art of making spiral wound polymeric heat exchangers andU.S. Pat. No. 4,980,060 describes fusion bonded potting of porous hollowfiber tubes for filtration. Neither disclosure contemplates the use oftemperature control of such devices.

[0011] U.S. Pat. No. 5,216,743 teaches the use of a plurality ofthermoplastic compartments with individual heating elements in eachcompartment for heating water. Temperature sensors are in communicationwith a temperature controller to turn individual heating elements on oroff to maintain the desired water temperature. The invention does notcontemplate use in organic liquids, corrosive or oxidizing chemicals ofhigh purity for which it would be unacceptable to use such heatingelements. Similarly the thermoplastic compartments are relatively few innumber.

[0012] U.S. Pat. No. 5,748,656 discloses the use of a metalheat-exchange system for controlling the temperature of a lasing gas ina laser system using a heat-exchanger, a temperature sensor, amicroprocessor controller, and a proportioning valve to control the flowof heat exchange fluid as a way to control the temperature of the lasergas. While such an invention is useful for controlling the temperatureof gases, such a heat exchange system would have limited use forcontrolling the temperature of liquids. This is because of the muchhigher heat capacity and mass of liquids compared to gases. In addition,the corrosive nature of many liquids would preclude their use by such asystem. This invention does not contemplate use of the heat exchangerfor dispensing of controlled temperature and volumes of liquids.

[0013] Currently it is impractical to use thermoplastic heat exchangersto control the temperature of fluids because of the high expense andlarge size of devices needed. Metal heat exchangers are generallyunacceptable for use in semiconductor manufacturing because of thecorrosive nature of the chemicals and also the need to eliminatemetallic and particulate impurities from process liquids. What is neededis an apparatus for controlling and conditioning the temperature ofdispensed liquid volumes or recirculating liquid systems. The systemshould have fast response to temperature change, be chemically inert,have high surface area, and minimal volume.

SUMMARY OF THE INVENTION

[0014] The present invention provides for a high surface areathermoplastic heat exchanger device coupled to a fluid flow circuit witha temperature sensor, fluid control valve, and a microprocessorcontroller. The apparatus is useful for conditioning the temperature offluids used in recirculation baths and fluid dispense applications.

[0015] In a preferred practice of this invention, perfluorinatedthermoplastic hollow tubes, fibers, or filaments are used in the heatexchanger of this invention. The filaments are made of polymers such aspoly(tetrafluoroethylene-co-perfluoro(alkylvinylether)),poly(tetrafluoroethylene-cohexafluoropropylene), or blends thereof. Thehollow tubes are fusion bonded to form a unitary end structure or aunified terminal end block with a perfluorinated thermoplastic resin anda housing. In this structure the hollow tubes are fluid tightly bondedto the thermoplastic resin.

[0016] In the preferred practice of the invention the hollow tubescontained in the housing are braided, plaited, or twisted to createcords of the hollow tubes, fibers, or filaments prior to fusion bonding.The cords are thermally annealed to set the crest or bend of the cords.A cord is referred to in the practice of this invention as one or morehollow tubes, fibers, or filaments which have been twisted, plaited, orbraided, and laid parallel to form a unit which can be potted oralternately fusion bonded into the housing. Cords of thermally annealedhollow tubes gives the exchanger a high packing density, high heattransfer surface area, enhanced flow distribution, and a small volume.The heat exchange device is capable of operating with organic,corrosive, and oxidizing liquids at elevated temperatures. The heatexchanger has a housing with fluid inlet and outlet connections for theprocess and working fluids to be contacted across the walls of thehollow tubes. Contacting the fluids across the wall of the hollow tubesresults in exchange of energy between the process and working fluids.

[0017] In a one embodiment of the apparatus the heat exchanger iscoupled with a flow sensor, temperature sensor, and valve to enabledispense of controlled volumes of precisely temperature controlledliquids.

[0018] In a second embodiment the heat exchanger is placed in a fluidcircuit with a temperature sensor and a valve and a microprocessor tocontrol the temperature of a bath.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1. is a schematic view illustrating the apparatus comprisinga heat exchanger connected in-line with a fluid flow circuit, atemperature bath, and temperature control system of this invention tomaintain the temperature of a bath.

[0020]FIG. 2. is a schematic view illustrating the apparatus comprisinga heat exchanger connected in-line with a fluid flow circuit,temperature control bath, and temperature control system of thisinvention to provide measured volumes of temperature controlled liquidat a dispense point.

[0021]FIG. 3. is a schematic view illustrating the apparatus comprisinga heat exchanger connected in-line with a fluid flow circuit,temperature control system and source of heated water or steam toprovide controlled volumes of heated liquid at a dispense point.

[0022]FIG. 4. is a schematic view illustrating the apparatus comprisinga heat exchanger connected in-line with a fluid flow circuit,temperature control system and microwave energy source to providecontrolled volumes of heated liquid at a dispense nozzle.

[0023]FIG. 5. is a schematic diagram illustrating a microprocessorcircuit useful in controlling the temperature of the processs fluidusing the heat exchanger, valves and temperature sensors of thisinvention.

[0024]FIG. 6. is a schematic view illustrating a heat exchanger used ina preferred practice of this invention.

[0025]FIG. 7. is a graphical representation of a closed loop method ofuse of the apparatus of this invention described in Example 1.

[0026]FIG. 8. is a graphical representation of a dispense method of useof the apparatus of this invention described in Example 2.

DESCRIPTION OF SPECIFIC EMBODIMENT

[0027] This invention relates to a heat exchanger apparatus composed ofa plurality of thermoplastic heat exchange tubes potted into athermoplastic material. The exchange apparatus is coupled withtemperature sensors, control microprocessor, flow sensor, or optionallyvalves to control the temperature of a dispensed process fluid orchemical bath in real time. While the embodiments and examples of thisinvention are made with reference to water which is heated or cooled, itis to be understood that such illustrations are not limited to water asa fluid and heated solutions as a dispensed fluid. Other suitable fluidsfor heating and cooling include gases.

[0028] A schematic diagram illustrating the apparatus of the inventionis shown in FIG. 1. In this figure the flow of process fluid and workingfluid are shown flowing in a co-current fashion, however the fluids mayalso be made to flow in a counter current fashion. In the practice ofthis invention the heat exchanger 50 and temperature controller 46 areused to control the temperature of a re-circulation bath 12. The bath 12may be used to clean, strip, or coat substrates 18 as part of asemiconductor manufacturing process. A source of energy 24, for examplemegasonic or radiant energy, may be directed into the tank at through aprobe or lamp housing 14. Liquid in the bath may be circulated throughvalve 16, pump 26, and optionally flow controller for flow meter 28. Theliquid from the bath enters the heat exchanger 50 at inlet connection56, and flow through the device where it exchanges energy with fluid in72. The liquid from the bath leaves the exchanger at outlet 58, throughoptional valve 44, and is returned to the bath 12. Optional pressuretransducers 30 and 42, and temperature sensors 40 and 60 may beconnected to the fluid flow circuit conduit. A bypass containing valve20 can be used to adjust flow of bath liquid through the exchangeapparatus. The signal from a temperature sensor 22 passes to amicroprocessor-based controller 46, for example a CN7600 temperaturecontroller available from Omega Engineering, Stamford, Conn. Optionaltemperature sensor 48 measures the temperature of the fluid as it leavesthe exchanger at outlet 54. The controller 46 continually monitors thechange in the process fluid temperature from a desired set point andsends a signal to a valve 64 or a flow controller 36, or to the pump 68to varies the flow of fluid 72 into the heat exchanger 50 and tomaintain the temperature of the process fluid exiting the exchanger atprocess fluid outlet 58. The temperature of the fluid in 72 isconditioned by 78 through tubes 76 and 74. In this FIG. 78 is shown as achiller, but could also be a fluid heater. The fluid in 72 can berecirculated through the exchange apparatus through valve 70 and by pump68. The liquid from 72 flows through optional flow controller or flowmeter 36. In the fluid conduit inlet to fluid port 52 optionallycomprises valve 34, pressure transducer 38, and temperature sensor 32.Fluid from 72 exits the exchange apparatus at fluid port 54, and flowthrough the conduit with temperature sensor 48, pressure transducer 62,and proportioning valve 64. The fluid is returned back to 72. Anoptional bypass loop for 72 comprising valve 66 is useful for changingthe flow of liquid from 72.

[0029] The proportioning valve 64 permits continuous adjustment of theflow of water into the heat exchanger. An on-off valve can also be usedwith the advantage that it is simpler to operate and can control higherpressures of fluid. The proportioning valve is preferably a quick actingvalve and can be pneumatically actuated, voice coil actuated, orelectrically actuated. Examples of such valves include SMC valves,Entegris Teflon pneumatic valves. Suitable fluid flow controllers 36include gas mass flow controllers from Mykrolis Corporation, Billerica,Mass.; and liquid flow controllers from NT International, Chaska, Minn.A variable speed liquid pump useful in the practice of this invention isavailable from Cole-Parmer Instrument Company, Vernon Hills, Ill.

[0030] The temperature-sensing devices 22 and 48 are preferablyresistive temperature devices or thermocouples available from OmegaEngineering, Stamford, Conn. Alternatively thermistors can be used tomeasure the temperature.

[0031] An embodiment of this invention used to control the temperatureand volume of a process liquid which is dispensed is shown schematicallyin FIG. 2. In this figure the flow of process fluid and working fluidare shown flowing in a co-current fashion, however the fluids may alsobe made to flow in a counter current fashion. The heat exchangeapparatus 110 comprises a flow sensor 92 and a valve 128 to measure andcontrol the volume of thermally conditioned process fluid which isdispensed. The process fluid from a source 94 is heated or cooled by theworking or exchange fluid 84. A suitable liquid flow sensor 92 isavailable from NT International, Chaska, Minn. Fluid source 94 can bedelivered to the heat exchanger by a pressurized pot or a pressurizedNOW PAK®. Alternatively a pump, such as Intelligen®, MykrolisCorporation, Bedford, Mass., or White Knight pump, Hemlock, Mich. can beused to transport fluid from the source to the exchanger. The pump maybe installed prior to exchanger fluid connection 112, or after fluidexchanger connection 116. The temperature of the heated liquid ismonitored by temperature sensor 126 connected to a microprocessor-basedtemperature controller 130. An optional pressure transducer 124 may beinstalled at the exchanger outlet 116. The liquid is dispensed throughvalve 128 and onto a substrate. The valve 128 can be an on-off valve ora stop suck-back valve. Suitable stop-suck back valves are availablefrom CKD Corporation, Japan. The controller 130 is in communication witha heater or chiller 90 used to maintain reservoir 82 at a temperaturesuitable for the application. The temperature of the liquid in thereservoir 82 is conditioned by heater or cooling surface 84, and ismeasured with temperature sensor 91. This fluid is delivered to theexchange apparatus through valve 86, pump 96, and optional flowcontroller 104. After optional pressure transducer 106 and temperaturesensor 108, the fluid from 82 enters the exchange apparatus at fluidconnection 118. Energy is exchanged between the working and processfluids in the exchanger and fluid from 82 exits the exchanger a fluidconnection 114. Fluid flows through the conduit with optionaltemperature sensor 122, pressure transducer 115 and returns to 82.

[0032]FIG. 3 shows a schematic illustration of another configuration ofthe apparatus of this invention. A source of working or exchange fluid136 other than from a closed loop supply or reservoir is used. In thisfigure the flow of process fluid from a source 140 and working fluidfrom a source 136 are shown flowing in a co-current fashion, however thefluids may also be made to flow in a counter current fashion. Examplesof suitable working or exchange fluids 136 include chilled plant water,hot deionized water, or steam. These fluids are commonly available fromthe facilities of the semiconductor facility. Fluid from the source 136flows through optional valve 137, optional flow controller 138, andoptional pressure and temperature transduces 144 and 162. The fluid from136 enters the exchange apparatus where energy is transfer with processfluid from source 140. Working fluid 136 exits the exchange apparatusthrough outlet 156 and through optional pressure and temperaturetransducers 154 and 155 respectively. Working fluid from a source 140enters the exchange apparatus through a flow controller 146. Fluid fromsource 140 can optionally be delivered to the heat exchanger by apressurized pot or a pressurized NOW PAK®. Alternatively a pump, such asIntelligen®, Mykrolis Corporation, Bedford, Mass., or White Knight pump,Hemlock, Mich. can be used to transport fluid from the source to theexchanger. The pump may be installed prior to exchanger fluid connection151, or after fluid exchanger connection 157. Fluid from the source 140flows through the conduit and optional valve 148, optional pressuretransducer 150 and temperature sensor 142. Process fluid flows throughthe 158 where it exchanges energy with the working fluid from 136. Atemperature sensor 168 measures the temperature of the output fluid 140exiting the heat exchanger at fluid connection 157. Temperature sensor168 is in communication with microprocessor controller 170 which opensand closes valve 152 to regulate the flow rate of working fluid throughthe exchange device; this controls temperature of the process fluid 140exiting the heat exchanger. The liquid process fluid 140 is dispensedthrough valve 166 and onto a substrate. The valve 166 can be an on-offvalve or a stop suck-back valve.

[0033]FIG. 4 illustrates another embodiment of this invention forheating a process liquid for dispense which utilizes a source ofmicrowave energy 183 which encloses the hollow tubes. Perfluorinatedthermoplastic pipe, tubes and fibers are transparent to microwaves andare ideal for flow through heating of aqueous or other microwaveabsorbing liquids like alcohols. Working fluid from a source 182 entersthe exchange apparatus through a flow controller 184. Fluid from source182 can optionally be delivered to the heat exchanger 188 by apressurized pot or a pressurized NOW PAK®. Alternatively a pump, such asIntelligen®, Mykrolis Corporation, Bedford, Mass., or White Knight pump,Hemlock, Mich. can be used to transport fluid from the source to theexchanger. The pump may be installed prior to exchanger fluid connection189, or after fluid exchanger connection 191. Fluid from the source 182flows through the conduit and optional valve 185, optional pressuretransducer is 187 and temperature sensor 186. Process fluid flowsthrough the hollow tubes in the exchange apparatus and absorb microwaveenergy from the microwave system and source 183 enclosing the hollowtubes. A temperature sensor 190 measures the temperature of the outputfluid 182 exiting the heat exchanger at fluid connection 191.Temperature sensor 190 is in communication with microprocessorcontroller 180 which turns the microwave magnetron on or off; thiscontrols temperature of the process fluid 182 exiting the exchanger 188.Alternately the microprocessor controller 180 adjusts the power to themagnetron to control the temperature of the fluid by controlling theamount of microwave power generated. The liquid process fluid 182 isdispensed through valve 192 and onto a substrate. The valve 192 can bean on-off valve or a stop suck-back valve. Alternately, controller 180,in communication with temperature sensors 186 and 190, can be used tocontrol flow meter 184 and regulate the flow and temperature of liquid.

[0034]FIG. 5 illustrates a schematic diagram of a processor 249 capableof detecting the signals from one or more temperature sensors,processing the sensor signals into a suitable form, comparing thesensors measured temperature to a predetermined temperature setpoint,generating an electrical signal proportional to the difference betweenthe measured fluid temperature and the setpoint temperature, andsignaling dispense pumps, valves, flow meters, or process equipment tobecome activated based on the results of the comparison. The sourcecontrol 250, by communication with the control microprocessor 260,controls at least one generated electrical signal proportional to thetemperature difference between the measured fluid temperature and thefluid setpoint temperature. An electrical signal proportional to therate of change of the fluid temperature can also be determined by theprocessor 249. This electrical signal may be output as voltage orcurrent at connector 252 and is useful for controlling a fluid controlvalve or a fluid flow controller. Optionally the generated electricalsignal at connector 252 modulates power to a microwave generator 183 orother energy source surrounding the hollow tubes. This electrical signalmay also be used to control the temperature of the working or exchangefluid by modulating external heaters 90 or chiller 78. This arrangementcan be used to compensate for different fluid characteristics and forchanging dispense requirements. The signal conditioner 256 excites andaccepts one or more sensor inputs 254. The signal conditioner 256 mayamplify, filter, or average raw sensor output signal. Examples ofsensors useful in the present invention include temperature, flow,pressure, and pH. The multiplexer 258 allows for multiple inputreference voltages 282 and 284, which differ from the desired sensorsignals, to effect calibration or control functions of the processor249. The reference voltages 282 and 284 can be used for calibration andrun time compensation for environmental changes such as temperature offluid viscosity. The control processor 260 controls all input and outputinterfaces between the processor 249 and apparatus connected to theprocessor 249, including the trigger 262 which functions to start torecord and analyze functions a multiple or single input; acknowledgment264 which functions as signal support to equipment of a problem or taskcomplete as a multiple or single outputs; spinner 266 which functions tospin a wafer; and analog output 270 which functions to indicate to thewafer spin control that the dispense is complete and the high speed spincan begin. The input-output interface 272 allows for a hardwareconnection to the track or other support equipment for communicationsvia RS232, Device Net, RS485, or other digital protocol port 268. Theport 268 is useful for start and stop control, enabling specialequipment features, and determining system status. The power supply 274converts incoming voltage to the internal required voltage such as 5 VDCfor the processor and associated logic and analog supply voltage such as±15 VDC. The signal processor 276 obtains real time signal from theanalog to digital converter 278 and runs algorithms required for thedetermination of fluid dispense temperature and flow rate. The data fromthe analog to digital converter 278 can be sorted for future retrievaland analysis. The real time data signal from the sensor can be used asthe control signal for closed loop control of the volume, timing, andfluid temperature of a dispense.

[0035] In one embodiment a commercially available thermoplastic heatexchanger available from Ametek, Wilmington, Del., can be used. Othermethods for forming thermoplastic heat exchangers useful in the practiceof this invention are described in U.S. Pat. No. 3,315,750, U.S. Pat.No. 3,616,022, U.S. Pat. No. 4,749,031, U.S. Pat. No. 4,484,624, andCanadian Pat. No. 1,252,082 each of which is included by reference intheir entirety. The hollow filaments can also be joined to the housingby the injection molding method described in European Patent Application0 559 149 A1 included herein by reference in its entirety.

[0036] In a preferred embodiment, incorporated in its entirety byreference, Co-pending application filed concurrently herewith as U.S.Ser. No. 200100292PCT under Applicants reference number MYKP-620, isused in the practice of this invention. The heat exchanger comprisesmatted, braided, plaited, or twisted perfluorinated thermoplastic hollowtubes which have been thermally annealed to set the bends or crests ofthe hollow tubes in the plait. An example of such a device is shownschematically in FIG. 6. The apparatus has high heat transfer surfacearea of about 13 square feet in a small volume of about 1 liter and thethermally annealed plaited tubes eliminates the need for baffling.Perfluorinated thermoplastic hollow tubes are preferred in the practiceof this invention because of their chemical resistance and thermalstability. In this embodiment, the heat exchanger apparatus is formed ina unitary end structure or unified terminal end block structure withhollow tubes 328 and 330 fused to a thermoplastic resin at 316 and 320as shown in FIG. 6. Hollow tubes 328 and 330, which can also be referredto in the practice of this invention as hollow fibers or hollowfilaments, have been twisted and thermally annealed to set the bend ofthe tubes. The housing comprises a first fluid inlet fitting 312 andfirst fluid outlet fitting 326 on end caps 334 and 336. The end caps areoptionally fusion bonded to the housing 332 and unified terminal endblocks 316 and 320. The housing also comprises a shell side inletfitting 322, with optional insert 338 for shell side fluid flowdistribution and shell side outlet fitting 318 for shell side fluidoutlet. By way of illustration, a first liquid enters fluid fitting 312and enters hollow tubes at 314 where it contacts a surface of the tubesand flows through the tubes to hollow tube outlet 324 and exits firstfluid outlet fitting 326. A second fluid enters fluid connection 322where it contacts a second surface of the tubes and flows across thetubes to outlet connection 318. The first and second fluids exchangeenergy through the walls of the hollow tubes. The first and secondfluids are separated from each other by the housing 332 and unifiedterminal end blocks 316 and 320.

[0037] Examples of perfluorinated thermoplastics or their blends whichare useful in the practice of this invention for the hollow tubes andhousing include but are not limited to[Polytetrafluoroethylene-co-perfluoromethylvinylether], (MFA),[Polytetrafluoroethylene-co-perfluoropropylvinylether], (PFA),[Polytetrafluoroethylene-co-hexafluoropropylene], (FEP), and[polyvinylidene fluoride], (PVDF). Both PFA Teflon® and FEP Teflon®thermoplastics are manufactured by DuPont, Wilmington, Del. Neoflon® PFAis a polymer available from Daikin Industries. MFA Haflon® is a polymeravailable from Ausimont USA Inc. Thorofare, N.J. Preformed MFA Haflon®and FEP Teflon® tubes are available from Zeus Industrial Products Inc.Orangebury, S.C. Other thermoplastics or their blends which are usefulin the practice of this invention include but not limited topoly(chlorotrifluoroethylene vinylidene fluoride), polyvinylchloride,polyolefins like polypropylene, polyethylene, polymethylpentene, andultra high molecular weight polyethylene, polyamides, polysulfones,polyetheretherketones, and polycarbonates.

[0038] Hollow thermoplastic tubes can be impregnated with thermallyconductive powders or fibers to increase their thermal conductance.Examples of useful thermally conductive materials include but are notlimited to glass fibers, metal nitride fibers, silicon and metal carbidefibers, or graphite.

[0039] Perfluorinated thermoplastic tube filaments made from blends ofperfluorinated thermoplastics with outside diameters ranging from 0.007to 0.5 inches, and more preferably 0.025 to 0.1 inches in diameter, andwall thickness ranging from 0.001 to 0.1 inches, preferably 0.003 to0.05 inches in thickness, are useful for forming braided or twisted cordfor the exchanger. For purposes of this invention, a single, un-wrappedannealed tube is considered a non-circumferential tube.Non-circumferential tubes are tubes with external dimensions that arenot continuously circumferential on a longitudinal axis moving from oneend portion of the tube to the other. Examples include, but are notlimited to, a helical coil, a permanently twisted hollow circular tubingsuch as the single, un-wrapped annealed fiber or a tube that is extrudedin such condition, a triangular shaped tube or fiber, a rectangularshaped tube or fiber, or a square shaped tube or fiber.

[0040] The braid, plait, twist, or non-circumfrential geometry of thehollow tubes or fibers provides for enhanced fluid distribution acrossand within the hollow tubes. The device provides high fluid contactingarea in a small volume without the need for baffles. The unitary orunified terminal block construction of the apparatus with chemicallyinert materials of construction eliminates the need for o-rings andpermits use of operation of the device at elevated temperatures and witha variety of fluids.

EXAMPLE 1

[0041] Preformed MFA tube filaments with 0.047 inch inside diameter and0.006 inch thick wall thickness were from Zeus Industrial Products Inc.Orangebury, S.C. Cord for potting were made by twisting the MFAfilaments to obtain 12 turns per foot of strand. A single strand waswrapped around a metal frame 8 inches wide and 18 inched long. The frameand wrapped strand were annealed in an oven for 30 minutes at 150degrees Celsius. About 75 cords measuring 18 inches in length wereobtained from the rack aster annealing. Cord from multiple racks aregathered to yield 310 cords and placed into a previously heat treatedand MFA coated PFA tube measuring 16 inches in length. The insidediameter of the PFA was 2 inches and fluid fittings were bonded 2 inchesfrom each end of the PFA tube. Each end of the device was potted usingHyflon® MFA 940 AX resin, obtained from Ausimont USA Inc. Thorofare,N.J., for about 40 hours at 275° C. Cool down of each end after 40 hoursof potting was controlled to a rate of 0.2° C. per minute to 150° C. toprevent stress cracking. The ends were cleared of resin and thefilaments opened by machining the end portion of the potted device usinga lathe. Fluid fittings for the potted exchanger were made by scoring apipe thread onto each end of the tube.

[0042] Test setup shown in FIG. 1 consisted of fluid flow through pump26 of 7.2 liters per minute and exchange fluid flow of 6.2 liters perminuted at about 25° C. Two 1000 watt heaters were placed in the 45liter volume bath 12. With 6.2 liters per minute 25° C. water flowthrough fittings 52 and 54 the temperature of the bath was maintained atabout 34° C. When cool water flow was stopped, the temperature of thebath 12 increased to 41° C. Use of an Omega Engineering controller modelnumber CN76000 with a resistive temperature sensor, 22, in the bathenabled control of the bath temperature to setpoint 1 of 38° C. and setpoint two of 39.5° C. The controller was connected to a pneumatic valve64 via an electrically actuated solenoid valve, not shown, pressurizedto 80 pounds per square inch. The controller opened and closed the valvein response to the electrical signal from the controller. The resultsfrom this example are shown in FIG. 7.

EXAMPLE 2

[0043] Preformed MFA tube filaments with 0.047 inch inside diameter and0.006 inch thick wall thickness were from Zeus Industrial Products Inc.Orangebury, S.C. Cord for potting were made by twisting the MFAfilaments to obtain 12 turns per foot of strand. A single strand waswrapped around a metal frame 8 inches wide and 18 inched long. The frameand wrapped strand were annealed in an oven for 30 minutes at 150degrees Celsius. About 75 cord measuring 18 inches in length wereobtained from the rack after annealing. Cord from multiple racks aregathered to yield 310 cords. They were placed into a previously heattreated and MFA coated PFA tube measuring 16 inches in length. Theinside diameter of the tubes was 2 inches and fluid fittings were bonded2 inches from each end of the PFA tube. Each end of the device waspotted using Hyflon® MFA 940 AX resin, obtained from Ausimont USA Inc.Thorofare, N.J., for about 40 hours at 275° C. Cool down of each endafter 40 hours of potting was controlled to a rate of 0.2° C. per minuteto 150° C. to prevent stress cracking. The ends were cleared of resinand the filaments opened by machining the end portion of the potteddevice using a lathe. Fluid fittings for the potted exchanger were madeby scoring a pipe thread onto each end of the tube. Two devices wereconfigured in series with the outlet of fluid from the tubes of a firstheat exchanger feeding the inlet fitting to the tubes of the second heatexchanger.

[0044] The test setup is illustrated in FIG. 2. Flow meter 92 from NTInternational, and electrical valve 98 from Entegris were connected toheat exchanger 110 upstream of the fluid fitting 112. Heated exchangefluid contained in reservoir 82 was prepared by heating a 60 literreservoir of water with three 1000 watt heaters to a temperature of 70°C. Process liquid water at a temperature of 23° C., 94, was fed into theheat exchanger for contact and exchange of energy with the 70° C.working fluid through the walls of the hollow tubes. A dispenseconsisted of about 330 milliliter volume of water delivered at a flowrate of about 22 milliliters per second for 15 seconds. The processwater was dispensed by opening and closing valve 98. The results fromthis test are shown graphically in FIG. 8. The results show theapparatus of this invention can heat volumes of liquid from 23° C. toabout 65.7° C. in a repeatable manner.

1. An apparatus for conditioning the temperature of a fluid adapted tobe connected in-line with a fluid flow circuit comprising: a) aplurality of hollow tubes of a thermoplastic resin, each of said hollowtubes having a first surface, a second surface, and a wall between saidsurfaces, each hollow tube having two end portions and hollows passingtherebetween; b) at least one of said endportions of said hollow tubesbeing bonded at least at a portion of its second surface to form aterminal block in which the end portions of said hollow tubes are fluidtightly bonded together with the in a fused fashion; c) said hollowtubes being un-bonded at portions other than the end portions; d) saidunified terminal block having through hole communication with thehollows of the unbonded portions of said hollow tubes; e) a housingcontaining said hollow tubes, the housing providing separation of afirst fluid for contact with said first surface of said hollow tubesfrom a second fluid in contact with said second surface of said hollowtubes; f) said housing having at least on first fluid connection forflow through of a first fluid across a first surface of the hollowtubes, said first fluid to be contacted with a second fluid separatedfrom the first fluid by the wall of the hollow tubes; g) said housinghaving at least one second fluid connection for flow through of a secondfluid across a second surface of the hollow tubes, said second fluid tobe contacted with the first fluid and separated from the first fluid bythe wall of the hollow tubes; h) fluid flow controlling means in fluidcommunication with said second housing fluid connection; i) temperaturesensing means in fluid communication with said first fluid and in fluidcommunication with said first fluid connection for measuring thetemperature of the first fluid; and j) an electronic circuit means fordetermining the temperature of the first fluid, comparing said measuredfirst fluid temperature to a predetermined setpoint temperature for saidfirst fluid, generating an electrical output signal proportional to thedifference between the first fluid setpoint temperature and the measuredfirst fluid temperature.
 2. The apparatus of claim 1 further comprising:electronic circuit means wherein the generated electrical output signalproportional to the difference between the first fluid setpointtemperature and the measured first fluid temperature is used to changethe fluid flow through the flow controlling means for the second liquid.3. The apparatus of claim 1 further comprising: electronic circuit meanswherein the generated electrical output signal proportional to thedifference between the first fluid setpoint temperature and the measuredfirst fluid temperature is used to change the temperature of a source ofthe second fluid until the temperature of the first fluid issubstantially equal to the first fluid temperature setpoint.
 4. Theapparatus of claim 1 further comprising: electronic circuit meanswherein the generated electrical output signal proportional to thedifference between the first fluid setpoint temperature and the measuredfirst fluid temperature is used to control the output from a source ofenergy enclosing the hollow tubes.
 5. The apparatus of claim 1 furthercomprising: electronic circuit means wherein the generated electricaloutput signal proportional to the difference between the first fluidsetpoint temperature and the measured first fluid temperature is used tochange the flow rate of a source of the first fluid until thetemperature of the first fluid is substantially equal to the first fluidtemperature setpoint.
 6. The apparatus of claim 1 further comprising: avalve for control of the dispense of a volume of fluid onto a substrate.7. The apparatus of claim 1, wherein said heat exchanger is comprised ofpoly(tetrafluoroethylene-co-perfluoro(alkyvinylether)),poly(tetrafluoroethylene-co-hexafluoropropylene), MFA, polypropylene,polymethylpentene, ultra high molecular weight polyethylene orco-polymers thereof.
 8. The apparatus of claim 1, wherein said hollowtubes are non-circumfrential.
 9. The apparatus of claim 1, wherein saidhollow tubes are plaited into cords and thermally annealed.
 10. Theapparatus of claim 1 wherein said thermoplastic hollow tubes areimpregnated with a thermally conductive material.
 11. The apparatus ofclaim 1 wherein said first fluid is a photoresist, antireflectivecoating, or a photoresist developer.
 12. The apparatus of claim 1wherein said first fluid is a spin on dielectric.
 13. The apparatus ofclaim 1 wherein said first fluid is a solution comprising copper ions.14. The apparatus of claim 1 wherein said fluid is chosen from the groupconsisting of acids, bases, oxidizers, or abrasive slurry.
 15. Theapparatus of claim 1 wherein said liquid is a photoresist stripper. 16.The apparatus of claim 1 wherein said liquid is an organic liquid. 17.The apparatus of claim 1 further comprising fluid flow controlling meansin fluid communication with said first housing fluid connection.
 18. Theapparatus of claim 17 wherein the fluid flow controlling means is adispense pump, valve, fluid flow controller, or pressure pot.
 19. Amethod for maintaining the temperature of a liquid, a temperature sensorpositioned to read the temperature of said first fluid and whichgenerates a temperature signal indicative of the first fluidtemperature, and a thermoplastic heat exchanger positioned to add orremove heat from the first fluid, said method comprising comparing thefirst fluid temperature as indicated by the temperature signal to aset-point and adjusting the instantaneous rate of addition or removal ofheat through the heat exchanger to maintain the temperature of the firstfluid in the fluid circuit, as read by the temperature sensor,essentially constant. Controlling the flow of said second fluid throughsaid heat exchanger by passing the second fluid through a flowproportioning valve and regulating the flow of said second fluid usingsaid flow proportioning valve.
 20. The method of claim 19 wherein thetemperature sensor is located in a wafer cleaning bath.
 21. The methodof claim 19 wherein the temperature sensor is in fluid communicationwith the dispense nozzle of a flow circuit.
 22. The method of claim 19wherein the temperature sensor is located in the flow circuit.
 23. Themethod of claim 19 wherein the temperature sensor is a thermocouple,resistive temperature device, or thermistor.
 24. The method of claim 19wherein the process liquid is a photoresist.
 25. The method of claim 19wherein the process liquid contains an organic liquid.
 26. The method ofclaim 19 wherein the process liquid contains copper ions.
 27. The methodof claim 19 wherein the process liquid comprises an aqueous acid, base,oxidizer, or abrasive.
 28. The method of claim 19 wherein the functionof adjusting the instantaneous rate of addition or removal of heatthough the heat exchanger to maintain the temperature of the processliquid in the fluid flow circuit, as read by the temperature sensor,essentially constant is performed by a source of microwaves.
 29. Amethod for controlled heat transfer from a first liquid to a secondfluid the method comprising: contacting the first fluid with athermoplastic heat exchanger; and contacting the thermoplastic heatexchanger with a second fluid for adding or removing heat from saidfirst liquid through the thermoplastic exchanger; wherein the heatexchanger surface area per unit volume of exchanger space is 1200 m²/m³or greater.
 30. A heat exchange apparatus and controller for adding orremoving heat, the apparatus comprising a heat exchanger including aheat exchange surface area per unit volume of exchanger space of 1200m²/m³ or greater.
 31. A closed loop heat exchange apparatus for addingor removing heat, the apparatus comprising a thermoplastic heatexchanger and closed loop temperature circuit including temperaturesensors for sensing a first and second fluid flow, an electronic circuitand second fluid heat transfer controller, whereby the closed loopcircuit operates by sensing the temperature in the first and secondfluid flows and the electronic circuit receives signals proportional tothe first and second fluid flow temperatures; the flow of the secondfluid or the temperature of the second liquid being adjusted until thetemperature of the first liquid is substantially equal to the desiredfirst fluid temperature.